Novel compound and organic electronic device using the same

ABSTRACT

A novel compound is disclosed, which comprises: a 7-membered ring segment, which is formed by a cis-stilbene segment and a bridge atom with four bonds; and an acridine segment connecting to the bridge atom of the 7-membered ring segment. In addition, an organic electronic device is also disclosed, and an organic layer therein comprises the novel compound of the present invention.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of filing date of U.S. Provisional Application Ser. No. 62/200,929, entitled “Compound for Organic light-emitting diode” filed Aug. 4, 2015 under 35 USC §119(e)(1).

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a novel compound and an organic electronic device using the same and, more particularly, to a novel compound as dopant emitters and emitters for OLEDs and an organic electronic device using the same.

2. Description of Related Art

It is well known that organic light emitting diode (OLED) was initially invented and proposed by Eastman Kodak Company through a vacmun evaporation method. Tang and VanSlyke of Kodak Company deposited an electron transport material such as Alq₃ on a transparent indium tin oxide (abbreviated as ITO) glass formed with an organic layer of aromatic diamine thereon, and subsequently completed the fabrication of an organic electroluminescent (EL) device after a metal electrode is vapor-deposited onto the Alq₃ layer. The organic EL device currently becomes a new generation lighting device or display because of high brightness, fast response speed, light weight, compactness, true color, no difference in viewing angles, without using any LCD backlight plates, and low power consumption.

Recently, some interlayers such as electron transport layer and hole transport layer are added between the cathode and the anode for increasing the current efficiency and power efficiency of the OLEDs. For example, an organic light emitting diode (OLED) 1′ shown as FIG. 1 is designed to consist of: a cathode 11′, an electron injection layer 13′, a light emitting layer 14′, a hole transport layer 16′, and an anode 18′.

In device function concept, the light emitted by the OLED 1′ is resulted from excitons produced by the recombination of electrons and holes in the light emitting layer 14′. However, according to theoretical speculation, the ratio of the excitons with singlet excited state and the excitons with triplet excited state is 1:3. So that, when a small molecular fluorescent material is used as the light-emitting layer 14′ of the OLED 1′, there are about 25% excitons being used in emitting light, and the rest of 75% excitons with triplet excited state are lost through non-luminescence mechanism. For this reason, the general fluorescent material performs a maximum quantum yield of 25% in limit which amounts to an external quantum efficiency of 5% in the device.

Moreover, researches further find that certain hole transport type material can simultaneously perform electron confining ability, such as the material represented by following chemical formulas 1′ and 2′. The chemical formula 1′ represents the chemical structure of Tris(4-carbazoyl-9-ylphenyl)amine, which is called TCTA in abbreviation. The chemical formula 2′ represents the chemical structure of N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine called NPB in abbreviation.

In addition, for effective blue-emitting performances in OLED applications, researchers have developed hole-transporting type, blue-emitters based on triarylamine dimer regimes, such as IDE-102, N-STIF-N, and spirobifluorene-based systems. These materials are represented by the following chemical formulas 3′, 4′, and 5′.

Recently, for effectively increasing the lighting performance of OLEDs, OLED manufactures and researchers have made great efforts to develop electron transport materials with hole blocking fiunctionality, such as TmPyPb, TPBi, 3TPYMB, BmPyPb, and DPyPA represented by following chemical formula 6′-10′, respectively. Wherein TmPyPb is the abbreviation of 3,3′-[5′-[3-(3-Pyridinyl)phenyl][1,1′: 3′,1″-terphenyl]-3,3″-diyl]bispyridine, TPBi is the abbreviation of 1,3,5-Tris(1-phenyl-1H-benzimidazol-2-yl)benzene, 3TPYMB is the abbreviation of Tris(2,4,6-triMethyl-3-(pyridin-3-yl)phenyl)borane, BmPyPb is the abbreviation of 1,3-bis(3,5-dipyridin-3-yl-phenyl)benzene, and DPyPA is the abbreviation of 9,10-bis(3-(pyridin-3-yl)phenyl) anthracene.

In spite of various blue emitting dopant materials and emitters with electron blocking functionality have been developed, the fluorescent OLEDs applied with the said blue dopant materials still cannot perform outstanding luminous efficiency and device lifetime. Accordingly, in view of the conventional or commercial blue emitting dopant materials and emitters with electron blocking and triplet-triplet annihilation (TTA) functionality still including drawbacks, the inventor of the present application has made great efforts to make inventive research thereon and eventually provided a series of novel compounds for OLEDs.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a novel compound suitable for an organic electronic device.

Another object of the present invention is to provide an organic electronic device using the novel compound of the present invention.

To achieve the object, the compound of the present invention comprises: a 7-membered ring segment, which is formed by a cis-stilbene segment and a bridge atom with four bonds; and an acridine segment connecting to the bridge atom of the 7-membered ring segment.

In one aspect of the present invention, the bridge atom is C or Si.

In one preferred aspect of the present invention, the compound is represented by the following formula (I):

wherein, each of R₁ and R₂ independently is halogen. C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy, C₃-C₂₀ cycloalkyl, C₃-C₂₀ heterocycloalkyl, —NR_(a)R_(b), —CN, aryl, heteroaryl, carbazoyl, or —R_(c)-R_(d); each of R₃, R₄ and R₅ independently is H, halogen, C₁-C₁₀ alkyl, C₁-C₁₀ alkenyl, C₁-C₁₀ alkoxy, C₃-C₂₀ cycloalkyl. C₃-C₂₀ heterocycloalkyl, —NO₂, —OH, —NR_(a)R_(b), —CN, aryl, or heteroaryl; and Ar is an aromatic ring, wherein each of R_(a) and R_(b) independently is H, C₁-C₁₀ alkyl or aryl; R_(c) is aryl; and R_(d) is H, C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy, —CN or aryl.

In one aspect of the present invention, R₁ and R₂ are the same.

In another aspect of the present invention. R₁ and R₂ can be —NR_(a)R_(b), and R_(a) is aryl, and R_(b) is C₁-C₁₀ alkyl or aryl. Preferably, each of R_(a) and R_(b) independently is phenyl, naphthyl, or anthryl unsubstituted or substituted with C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy or —CN; and R_(b) is C₁-C₁₀ alkyl or phenyl, naphthyl, or anthryl unsubstituted or substituted with C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy or —CN. More preferably, R_(a) is phenyl unsubstituted or substituted with C₁-C₆ alkoxy or unsubstituted naphthyl; and R_(b) is C₁-C₆ alkyl, phenyl unsubstituted or substituted with C₁-C₆ alkoxy or unsubstituted naphthyl. Most preferably, R₁ and R₂ are the same —NR_(a)R_(b) substituents; wherein R_(a) is phenyl unsubstituted or substituted with C₁-C₆ alkoxy or unsubstituted naphthyl; and R_(b) is C₁-C₆ alkyl, phenyl unsubstituted or substituted with C₁-C₆ alkoxy or unsubstituted naphthyl.

In another aspect of the present invention. R₁ and R₂ can be the following substituent (II-1):

wherein X may be H or C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy, or CN. Preferably, X is H or C₁-C₆ alkyl C₁-C₆ alkoxy, or CN. More preferably, X is H, methyl ethyl, methoxy, or ethoxy. Most preferably, R₁ and R₂ are the same and selected from the group consisting of the substituents (II-1), wherein X is H, methyl, ethyl, methoxy, or ethoxy.

In another aspect of the present invention, R₁ and R₂ can be halogen. Preferably, R₁ and R₂ are Br.

In another aspect of the present invention, R₁ and R₂ can be aryl or heteroaryl. Preferably, R₁ and R₂ are pyridyl, phenyl, naphthyl, anthryl or carbazoyl. More preferably, R₁ and R₂ are the same substituents of pyridyl, phenyl, naphthyl, anthryl or carbazoyl.

In another aspect of the present invention, R₁ and R₂ can be phenyl unsubstituted or substituted with methoxy, ethoxy, or —CN. Preferably, R₁ and R₂ are phenyl unsubstituted or substituted with methoxy. More preferably, R₁ and R₂ are the same substituents of phenyl unsubstituted or substituted with methoxy.

In another aspect of the present invention, R₁ and R₂ can be —R_(c)-R_(d), in which R_(c) is phenylene, R_(d) is phenyl unsubstituted or substituted with methoxy, ethoxy, or —CN. Preferably, R₁ and R₂ are —R_(c)-R_(d), in which R_(c) is phenylene. R_(d) is phenyl unsubstituted or substituted with —CN. More preferably, R₁ and R₂ are the same substituents of —R_(c)-R_(d), in which R_(c) is phenylene. R_(d) is phenyl unsubstituted or substituted with —CN.

In further another aspect of the present invention, the compound of the formula (I) is represented by the following formula (I-1):

Preferably, the compound of the formula (I) is represented by the following formula (I-2):

More preferably, the compound of the formula (I) is represented by the following formulas (III-1) to (III-12):

The present invention provides a novel compound, which is constructed by at least one cis-stilbene based component and at least one acridine based component. The compound provided by the present invention has good thermal stability, wherein the glass transition temperatures (T_(g)) thereof is ranged from 118° C. to 163° C., and the decomposition temperatures (T_(d)) thereof is ranged from 400° C. to 465° C. In addition, the compound provided by the present invention also has several properties, such as reversible hole and/or electron transport properties, and balanced charges motilities; but the properties thereof are not limited thereto since the properties thereof can be adjusted by changing the substituents of R₁, R₂, R₃, R₄, R₅ and Ar.

Herein, the compounds of the present invention have oxidation potentials ranged from 0.06 V to 0.87 V or have the reduction potential ranged from-1.89 to-2.32 V. Additionally, the compound of the present invention has highest occupied molecular orbital energy levels (E_(HOMO)) ranged from 4.86 eV to 5.47 eV and lowest unoccupied molecular orbital energy levels (E_(LUMO)) ranged from 2.16 eV to 2.74 eV. However, the oxidation potentials, E_(HOMO) and E_(LUMO) of the compounds provided by the present invention are not limited to the values illustrated above, and can be adjusted by changing the substituents of R₁, R₂, R₃, R₄, R₅ and Ar.

Since the compound provided by the present invention has the aforementioned properties, it can be used in an organic electronic device. Hence, the present invention also provides an organic electronic device, which comprises: a first electrode; a second electrode; and an organic layer disposed between the first electrode and the second electrode, and comprising the compound provided by the present invention.

The application of the organic electronic device of the present invention comprises, but is not limited to an organic light emitting device, an organic solar cell device, an organic thin film transistor, an organic photodetector, a flat panel display, a computer monitor, a television, a billboard, a light for interior or exterior illumination, a light for interiror or exterior signaling, a heads up display, a fully transparent display, a flexible display, a laser printer, a telephone, a cell phone, a tablet computer, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display, a vehicle, a large area wall, a theater or stadium screen, or a sign. Preferably, the organic electronic device of the present invention is applied to an organic light emitting device or an organic solar cell device.

When the organic electronic device of the present invention is used as an organic solar cell device, the organic layer is a carrier transport layer.

When the organic electronic device of the present invention is used as an organic light emitting device, such as an organic light emitting diode (OLED), the compound of the present invention can be used as hole-transporters, electron-transporters or light-emitting materials due to the hole transport property, the reversible electron transport property, and the balanced charges motilities thereof. In this case, the organic layer can be a hole transport layer, an electron transport layer or a light emitting layer. In addition, the types the OLEDs capable of using the compound of the present invention is not particularly limited; and preferably, the compound of the present invention is applied in fluorescent or phosphorescent OLEDs for being as a hole transport layer, an electron transport layer, and/or a hole transport type emitting layer.

In the present invention, a variety of experimental data have proved that the compound of the present invention can indeed be used as hole-transporters, electron-transporters or emitting materials for OLEDs; moreover, the experimental data also reveal that the OLEDs using the compound of the present invention can indeed be used as the emitters and dopant emitters and are able to show good to excellent external quantum efficiency (η_(ext)), current efficiency (η_(e)), power efficiency (η_(p)), maximum luminance (L_(max)), and device lifetime comparable or better than those of OLEDs based on the commercial emitters or dopant materials.

In the present invention, alkyl, alkoxy, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl present in the compounds include both substituted and unsubstituted moieties, unless specified otherwise. Possible substituents on alkyl, alkoxy, cycloalkyl heterocycloalkyl, aryl, and heteroaryl include, but are not limited to, alkyl, halogen, alkoxy, heterocyclic group or aryl; but alkyl cannot be substituted with alkyl.

In the present invention, the term “halogen” includes F, Cl, Br and I; and preferably is F or Br. The term “alkyl” refers to linear and branched alkyl; preferably, includes linear or branched C₁₋₁₀ alkyl; and more preferably, includes linear or branched C₁₋₆ alkyl. Specific examples of alkyl include, but are not limited to, methyl, ethyl, n-propyl, iso-propyl, n-butyl, sec-butyl, iso-butyl, tert-butyl, pentyl, neo-pentyl or hexyl. The term “alkoxy” refers to a moiety that the alkyl defined in the present invention coupled with an oxygen atom; preferably, includes linear or branched C₁₋₁₀ alkoxy; and more preferably, includes linear or branched C₁₋₆ alkoxy. Specific examples of alkoxy include, but are not limited to, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy, pentyloxy, neo-pentyloxy or hexyloxy. The term “cycloalkyl” refers to a monovalent saturated hydrocarbon ring system having 3 to 20 carbon atoms; and preferably having 3 to 12 carbon atoms. Specific examples of cycloalkyl include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl. The term “heterocyclic group” refers to a 5-8 membered monocyclic, 8-12 membered bicyclic or 11-14 membered tricyclic heteroaryl or heterocycloalkyl having at least one heteroatom which is selected from the group consisting of O, S and N. Specific examples of heterocyclic group include, but are not limited to, pyridyl, pyrimidinyl, furyl, thiazolyl, imidazolyl or thienyl. The term “aryl” refers to a monovalent 6-carbon monocyclic, 10-carbon bicyclic, or 14-carbon tricyclic aromatic ring system. Specific examples of aryl include, but are not limited to, phenyl, naphthyl, pyrenyl, anthracenyl or phenanthryl; and preferably, the aryl is phenyl.

Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an OLED device of the prior art;

FIG. 2 is a perspective view showing an OLED device of the present invention; and

FIG. 3 is a perspective view showing an organic solar cell device of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention has been described in an illustrative manner, and it is to be understood that the terminology used is intended to be in the nature of description rather than of limitation. Many modifications and variations of the present invention are possible in light of the above teachings. Therefore, it is to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

Example 1 Preparation of Compound of Formula (III-6′)

The compound of the formula (III-6′) was prepared by using the following steps.

30 mM 2-bromo-triphenylamine of 37.5 mL was dissolved in 100 mL of anhydrous tetrahydrofuran (THF), and the obtained solution was placed in an environment of −78° C. for standing. Then, 12 mL of n-butyllithium in hexanes solution (30 mM) from a n-butyllithium solution 2.5 M in hexanes was added dropwise into the solution and the obtained reaction mixture was stirred for 30 min. 20 mM 3,7-dibromo-dibenzosuberenone (7.32 g 3,7-dibromo-dibenzosuberenone) dissolved in 20 mL of anhydrous THF was added into the reaction mixture dropwise, 10 mL of saturated aqueous sodium bicarbonate solution was added into the reaction mixture for executing a quenching reaction, and then THF was removed by rotary evaporation. The obtained product was treated with an extracting process by using dichloromethane, and an liquid extract was obtained. Then, 5 g magnesium sulfate was added into the liquid extract, the extract liquid extract was treated with a filtering process and a drying process sequentially, and the product was treated with a rotary evaporating process to obtain an intermediate product.

The following steps can be used for obtaining a clear crystalline intermediate product.

The obtained intermediate product was dissolved in 60 ml acetic acid, followed by adding 0.6 mL of concentrated hydrochloric acid (12 N) therein. The reaction mixture was reacted for 16 hours at 120° C. by using a reflux device, and then cooled down to 0° C. 60 mL hexane was added into the reaction mixture, and a Buchner funnel is used to treat the reaction mixture with a filtering process to obtain a precipitate. The precipitate was washed with hexane for 3 times to obtain a solid material. The solid material was treated with a recrystallization process by using dichloromethane/hexane to obtain a clear crystal solid, which is represented by the formula (III-6′).

Data for the compound of the formula (III-6′): m.p. 335.2° C. (DSC); M.W.: 591.33; ¹H NMR (500 MHz, CDCl₃) δ 6.25 (d, J=8.0, 2H), 6.48 (s, 2H), 6.68 (t, J=8.0, 2H), 6.87 (td, J=8.0, 1.2, 2H), 7.02 (d, J=8.0, 2H), 7.09-7.16 (m, 4H), 7.32 (d, J=1.6, 2H), 7.45 (d, J=8.0, 2H), 7.56 (t, J=8.0, 1H), 7.69 (t, J=8.0, 2H); HR-MS calcd for C₃₃H₂₁Br₂N: 589.0041. found: 589.0053. Anal. Calcd for C₃₃H₂₁Br₂N: C, 67.03; H, 3.58; N, 2.37. found: C, 67.25; H, 3.62; N, 2.25; TLC R_(f) 0.40 (CH₂Cl₂/hexane, 1/3).

Hereinafter, various exemplary compounds of the present invention can be fabricated by treating certain chemical reaction method to the key intermediate product of clear crystalline materials represented by the chemical formula (III-6′), such as Hartwig coupling reactions.

Example 2 Preparation of Compound of Formula (III-1′)

The compound of the formula (III-1′) was prepared via the following scheme I.

First, the compound of the chemical formula (III-6′) (99%) 4730.8 mg (8 mmol), Pd₂(dba)₃ (135 mg, 0.15 mmol), sodium tert-butoxide (2304 mg, 24 mmol), dppf (108 mg, 0.18 mmol) and diphenylamine (3046 mg, 18 mmol) was dissolved in toluene 200 mL under nitrogen gas, followed by refluxing the obtained mixture for 18 hours. Then, the reaction mixture was quenched with water (200 mL), and the aqueous layer was separated and extracted with CH₂Cl₂ (3×200 mL). The combined organic layers were dried (MgSO₄), filtered, and evaporated, and the obtained crude solid was re-crystallized from CH₂C₂/n-hexane to afford 2783 mg of a pure product, which is represented by the formula (III-1′).

Data for the compound of the formula (III-1′): T_(m) 318° C. (DSC); T_(g) 124° C.; M.W.: 767.98; ¹H NMR (400 MHz, CDCl₃) 7.38 (t, J=3.2 Hz, 3H), 7.16 (dd, J=7.6 2H), 7.04 (t, J=8.0 Hz, 8H), 6.97 (d, J=2.0 Hz, 2H), 6.91 (q, J=8.0 Hz, 6H), 6.78-6.74 (m, 10H), 6.70 (t, J=6.0 Hz, 2H), 6.54 (dd, J=8.4 Hz, 2H), 6.3 (s, 2H), 6.25 (m, 2H); ¹³C NMR (100 MHz, CDCl₃) 150.0, 146.7, 146.2, 140.5, 135.8, 135.4, 133.3, 132.2, 131.4, 130.5, 129.1, 127.8, 127.5, 125.7, 125.5, 124.5, 122.8, 120.5, 119.1, 114.1, 56.7; HR-MS calcd for C₅₇H₄₁N₃: 767.3300. found: 767.3312. Anal. Calcd for C₅₇H₄₁N₃: C, 89.15; H, 5.38; N, 5.47. found: C, 89.07; H, 5.32; N, 5.38; TLC R_(f) 0.2 (CH₂Cl₂/hexanes, 1/6).

Example 3 Preparation of Compound of Formula (III-2′)

The process for preparing the compound of formula (III-2′) is similar to that illustrated in Example 2, except the diphenylamine used in Example 2 was substituted with 4,4′-dimethoxydiphenylamine (4.15 g, 18 mmol) in the present example.

Data for the compound of the formula (III-2′): T_(m) 267° C. (DSC); T_(g) 127° C. (DSC); TLC R_(f) 0.30 (acetone/hexanes=1/4); ¹H NMR (400 MHz, CDCl₃) δ 3.70 (s, 12H), 5.84 (d, J=8.0, 2H), 6.25 (s, 2H), 6.32 (d, J=8.0, 2H), 6.43 (dd, J=8.0, 2.4, 2H), 6.62-6.88 (m, 24H), 7.14 (dd, J=8.0, 1.6, 2H), 7.42-7.45 (m, 3H); ¹³C NMR (100 MHz, CDCl₃) δ 55.28, 113.92, 114.42, 116.68, 120.45, 124.58, 125.20, 126.27, 126.88, 127.91, 129.04, 130.60, 131.20, 132.15, 133.37, 135.64, 135.86, 139.95, 140.55, 146.73, 149.90, 155.45; HR-MS calcd for C₆₁H₄₉N₃O₄: 887.3723 found: 887.3683.

Example 4 Preparation of Compound of Formula (III-3′)

A mixture of chemical formula III-6′ (2.50 g, 5.0 mmol), (3-cyanophenyl)boronic acid (1.628 g, 11.0 mmol), Pd(PPh₃)₄ (350 mg, 0.30 mmol), and sodium carbonate (2.70 g, 25 mmol) in DME (50 mL) and distilled water (10 mL) was refluxed for 24 h under argon. The mixture was then extracted with CH₂Cl₂. The combined organic extracts were dried over anhydrous MgSO₄ and concentrated by rotary evaporation. The crude product was purified by column chromatography on silica gel using 1:1 CH₂Cl₂/Hexanes as eluent to afford a greenish-yellow solid 2.09 g (yield, 76%).

Data for the compound of the formula (III-3′): T_(m) 293° C. (DSC); T_(g) 129° C. (DSC); TLC R_(f) 0.30 (dichloromethane/hexanes=1/1); ¹H NMR (400 MHz, CDCl₃) δ 7.69 (t, J=8.0, 2H), 7.53-7.57 (m, 7H), 7.40-7.46 (m, 4H), 7.21-7.33 (m, 8H), 6.86 (td, J=8.0, 0.8, 2H), 6.69 (td, J=8.0, 0.8, 2H), 6.64 (s, 2H), 6.26 (dd, J=8.0, 0.8, 2H); ¹³C NMR (100 MHz, CDCl₃) δ 149.81, 136.31, 136.24, 134.14, 133.12, 132.90, 131.81, 131.45, 130.97, 130.79, 130.16, 130.84, 129.50, 127.04, 124.16, 121.04, 118.70, 114.29, 114.21, 112.90, 57.52; HR-MS calcd for C₄₇H₂₉N₃: 635.2361. found: 635.2356.

Example 5 Preparation of Compound of Formula (III-4′)

The compound of the formula (III-4′) was prepared via the following scheme II.

First, the compound of the chemical formula (III-6′) (99%) 1182.7 mg (2.0 mmol), Pd (PPh₃)₄ (130 mg, 0.11 mmol), potassium carbonate (1105.7 mg, 8 mmol), and 4-pyridinylboronicacid (614.6 mg, 5 mmol), were dissolved in DMF/H₂O (30 mL/3 mL) under nitrogen gas, followed by refluxing the obtained mixture under 130° C. and stirring for 48 hours. Then, The reaction mixture was quenched with water (20 mL), and The aqueous layer was separated and extracted with CH₂Cl₂ (3×20 mL). The combined organic layers were dried (MgSO₄. ˜0.5 g), filtered, and evaporated; and the obtained crude solid was re-crystallized from CH₂Cl₂/n-hexane to afford 908.3 mg of a pure product, which is represented by the formula (III-4′).

Data for the compound of the formula (III-4′): T_(m) 430° C. (DSC); T_(g) 119.4° C.; T_(d): 428° C.; M.W.: 589.71; ¹H NMR (400 MHz, CDCl₃) 8.55 (d, J=6 Hz, 4H), 7.66 (t, J=7.6 2H), 7.62 (d, J=1.6 Hz, 2H), 7.56 (t, J=7.6 Hz, 2H), 7.35-7.3 (m 6H), 7.26-7.23 (m, 2H), 9.15 (dd, J=4.4 Hz, 4H), 6.88 (t, J=7.2 Hz, 2H), 6.71 (d, J=3.44 Hz, 2H), 6.67 (s, 2H), 6.27 (d, J=8.4 Hz, 2H); ¹³C NMR (100 MHz, CDCl₃) 150.17, 149.77, 147.51, 140.86, 137.08, 136.25, 133.98, 133.1, 132.95, 132.52, 131.34, 131.10, 128.68, 127.11, 124.23, 121.12, 121.03, 114.25, 77.25, 57.55; HR-MS calcd for C₄₃H₂₉N₃: 587.7105. found: 587.7100; TLC R_(f) 0.16 (Acetone/hexanes, 1/3).

Example 6 Preparation of Compound of Formula (III-5′)

A mixture of chemical formula (III-6′) (1.773 g, 3.0 mmol), cuprous cyanide (1.100 g, 12.0 mmol) in degasses DMF (12 mL) was refluxed for 18 h under argon. The mixture was then cooled to rt and concentrated under reduced pressure. An aqueous solution of ammonia (2M, 150 mL) was added and the mixture was extracted with CH₂Cl₂. The combined organic extracts were dried over anhydrous MgSO₄ (2.5 g) and concentrated by rotary evaporation. The crude product was purified by column chromatography on silica gel using 1:1 CH₂Cl₂/Hexanes as eluent to afford a yellow solid 0.986 g (yield: 68%).

Data for the compound of the formula (III-5′): T_(m) 348° C. (DSC); T_(g) 120° C. (DSC); TLC R_(f) 0.30 (EtOAc/hexanes=1/3); ¹H NMR (400 MHz, CDCl₃) δ 7.72 (t, J=8.0, 2H), 7.61-7.56 (m, 3H), 7.46 (d, J=8.0, 2H), 7.31-7.27 (m, 4H), 6.96 (dd, J=8.0, 1.2, 2H), 6.91 (td, J=8.0, 0.8, 2H), 6.69-6.65 (m, 4H), 6.29 (d, J=8.0, 2H); ¹³C NMR (100 MHz. CDCl₃) 8149.69, 140.86, 140.05, 136.66, 134.30, 132.71, 132.69, 132.58, 132.30, 131.32, 131.04, 128.83, 128.78, 127.85, 121.40, 118.66, 114.87, 112.05, 57.01; HR-MS calcd for C₃₅H₂₁N₃:483.1735. found: 483.1740.

Example 7 Preparation of Compound of Formula (III-7′)

The compound of the formula (III-7′) was prepared via the following scheme III.

30 mmol of 9-(2-bromophenyl)-carbazole of 9.63 grams was dissolved in 37.5 mL of anhydrous tetrahydrofuran (THF), and the obtained solution was placed in an environment of −78° C. for standing. Then, 18.8 mL of n-butyllithium in hexanes solution (30 mmol) from a n-butyllithium solution 1.6 M in hexanes was added dropwise into the solution and the obtained reaction mixture was stirred for 30 min. 20 mmol of 3,7-dibromo-dibenzosuberenone (7.32 g) dissolved in 20 mL of anhydrous THF was added into the reaction mixture dropwise. 10 mL of saturated aqueous sodium bicarbonate solution was added into the reaction mixture for executing a quenching reaction, and then THF was removed by rotary evaporation. The obtained product was treated with an extracting process by using dichloromethane (50 mL), and a liquid extract was obtained. Then, 5 g magnesium sulfate was added into the liquid extract, the liquid extract was treated with a drying process and a filtering process sequentially, and the product was treated with a rotary evaporating process to obtain an intermediate product.

The following steps can be used for obtaining a clear crystalline intermediate product.

The obtained intermediate product was dissolved in 60 ml acetic acid, followed by adding 0.6 mL of concentrated hydrochloric acid (12 N) therein. The reaction mixture was reacted for 16 hours at 120° C. by using a reflux device, and then cooled down to 0° C. 60 mL hexane was added into the reaction mixture, and a Buchner funnel is used to treat the reaction mixture with a filtering process to obtain a precipitate. The precipitate was washed with hexane (20 mL) for 3 times to obtain a solid material. The solid material was treated with a recrystallization process by using dichloromethane/hexane to obtain a clear crystal solid, which is represented by the formula (III-7′).

Data for the compound of the formula (III-7′): m.p. 342.6° C. (DSC); M.W.: 589.32; ¹H NMR (500 MHz, CDCl₃) δ 6.57 (s, 2H), 6.88 (d, J=0.2, 2H), 7.00-7.18 (m, 5H), 7.34-7.42 (m, 4H), 7.63 (t, J=8.0, 11), 7.84 (dd, J=8.0, 0.4, 1H), 8.17 (d. J=8.0, 1H), 8.23 (d, J=8.0, 1H), 8.29 (d, J=8.0, 1H); ¹³C NMR (100 MHz, CDCl₃) δ 57.25, 113.34, 113.37, 113.99, 114.03, 118.19, 118.25, 120.99, 121.04, 121.13, 121.17, 122.35, 122.40, 123.10, 123.77, 125.93, 125.99, 126.06, 126.82, 126.87, 128.20, 129.74, 130.68, 130.73, 130.77, 131.25, 131.29, 131.56, 131.78, 134.51, 134.56, 137.11, 138.29, 138.58, 138.87, 149.23; HR-MS calcd for C₃₃H₁₉Br₂N: 586.9884 found: 586.9879. HR-MS calcd for C₃₃H₂₁Br₂N: 586.9884. found: 586.9869. Anal. Calcd for C₃₃H₁₉Br₂N: C, 67.26; H, 3.25; N, 2.38. found: C, 67.21; H, 3.43; N, 2.28; TLC R_(f) 0.65 (CH₂Cl₂/hexane, 1/3).

Example 8 Preparation of Compound of Formula (III-8′)

First, the compound of the chemical formula (III-7′) (99%) 1.185 mg (2 mmol), Pd₂(dba)₃ (115 mg, 0.12 mmol), sodium tert-butoxide (768 mg, 8.0 mmol), dppf (91 mg, 0.16 mmol) and diphenylamine (742 mg, 4.4 mmol) was dissolved in toluene 20 mL under nitrogen gas, followed by refluxing the obtained mixture for 24 hours. Then, the reaction mixture was quenched with water (200 mL), and the aqueous layer was separated and extracted with CH₂Cl₂ (3×200 mL). The combined organic layers were dried (MgSO₄), filtered, and evaporated, and the obtained crude solid was re-crystallized from CH₂Cl₂/n-hexane to afford 1072 mg of a pure product, which is represented by the formula (III-8′).

Data for the compound of the formula (III-8′): T_(m) 259° C. (DSC); T_(g) 118° C. (DSC); TLC R_(f) 0.35 (dichloromethane/hexanes=1/2.5); ¹H NMR (400 MHz, CDCl₃) δ 6.35 (s, 2H), 6.41 (s, 1H), 6.60-6.62 (d, J=8.0, 10H), 6.70 (t. J=8.0, 4H), 6.86 (t, J=8.0, 8H), 6.93 (t, J=8.0, 1H), 7.00 (d, J=8.0, 2H), 7.11-7.16 (m, 2H), 7.28-7.38 (m, 4H), 7.47 (t, J=8.0, 1H), 7.68 (d, J=8.0, 1H), 7.72 (d, J=8.0, 1 H), 7.85 (d, J=8.0, 1 H), 8.06 (d, J=8.0, 1H); HR-MS calcd for C₅₇H₃₉N₃: 765.3144. found: 765.3118.

Example 9 Preparation of Compound of Formula (III-9′)

The compound of the formula (III-9′) was prepared via the following scheme IV.

In a pressure tube bis(4-methoxyphenyl)amine (5.04 g, 22 mmol), 3,7-dibromospiro[dibenzo[a,d][7]annulene-5,8′-indolo[3,2,1-de]acridine](5.90 g, 10 mmol) was mixed with sodium t-butoxide (4.66 g, 44 mmol), Pd(dba)₂ (dba=(1E,4E)-1,5-diphenylpenta-1,4-dien-3-one, 230 mg), 1,2-bis(diphenylphosphino)ferrocene, (220 mg) in toluene (100 mL) under nitrogen atmosphere. This was heated at 80° C. for 36 h. After the completion of the reaction the volatiles were removed by evaporation. The residue was triturated with water and extracted with dichloromethane. The combined organic layer was dried over anhydrous sodium sulfate and evaporated in vacuum to produce a crude product. It was adsorbed on silica gel and purified by column chromatography by using hexane/dichloromethane mixture as eluant. White solid; yield 6.21 g (70%)

Data for the compound of the formula (III-9′): T_(m) 236° C. (DSC); T_(g) 135° C. (DSC); TLC R_(f) 0.35 (dichloromethane/hexanes=1/2.5): ¹H NMR (400 MHz, CDCl₃) δ 3.63 (s, 12H), 6.24 (s, 2H), 6.35 (s, 2H), 6.42-6.50 (m, 10H), 6.53-6.57 (m, 7H), 6.93-6.97 (m, 3H), 7.13-7.19 (m, 2H), 7.28-7.38 (m, 4H), 7.48-7.51 (m, 1H), 7.72-7.74 (m, 2H), 7.91 (d. J=8.4 Hz, 1H), 8.07 (d, J=7.6 Hz, 1H); ¹³C NMR (100 MHz, CDCl₃) δ 155.6, 147.9, 147.3, 139.6, 139.4, 138.0, 134.4, 134.0, 133.9, 132.7, 131.1, 127.8, 127.5, 126.8, 126.4, 12.2, 125.9, 125.5, 123.3, 122.7, 121.6, 120.7, 119.3, 116.6, 116.5, 114.3, 113.3, 112.9, 57.6, 55.3; HR-MS calcd for C₆₁H₄₇N₃O₄: 885.3567. found: 885.3569.

Example 10 Preparation of Compound of Formula (III-10′)

A mixture of 3,7-dibromospiro[dibenzo[a,d][7]annulene-5,8′-indolo[3,2,1-de]acridine] (1.47 g, 2.5 mmol), (3-cyanophenyl)boronic acid (0.808 g, 5.5 mmol), Pd(PPh₃)₄ (144 mg, 0.12 mmol), and sodium carbonate (2.65 g, 25 mmol) in DME (50 mL) and distilled water (15 mL) was refluxed for 24 h under argon. The mixture was then extracted with CH₂Cl₂. The combined organic extracts were dried over anhydrous MgSO₄ and concentrated by rotary evaporation. The crude product was purified by column chromatography on silica gel using 1:1 CH₂Cl₂/Hexanes (R_(f)=0.3) as eluent to afford a greenish-yellow solid. Yield: 76%.

Data for the compound of the formula (III-10′): ¹H NMR (400 MHz, CDCl₃) δ 6.77 (s, 2H), 7.09 (s, 3H), 7.16-7.21 (m, 3H), 7.25-7.29 (m, 4H), 7.31 (s, 2H), 7.35-7.38 (m, 3H), 7.42 (d, J=7.6 Hz, 2H), 7.45-7.52 (m, 2H), 7.59-7.63 (m, 2H), 7.82 (d, J=8.0 Hz, 1H), 8.13 (d, J=7.6 Hz, 1H), 8.27 (d, J=8.4 Hz, 2H). ¹³C NMR (100 MHz, CDCl₃) δ 148.37, 141.46, 139.37, 138.20, 135.45, 135.35, 135.08, 133.55, 133.14, 132.25, 131.64, 130.83, 130.38, 129.65, 128.34, 127.18, 126.25, 126.08, 125.03, 123.79, 123.31, 122.58, 121.39, 121.35, 118.79, 118.28, 114.06, 113.43, 113.00, 58.29: HR-MS calcd for C₄₇H₂₇N₃ (633.2205) found: 633.2201.

Example 11 Preparation of Compound of Formula (III-11′)

The compound of the formula (III-11′) was prepared via the following scheme V.

A mixture of 3,7-dibromospiro[dibenzo[a,d][7]annulene-5,8′-indolo [3,2,1-de]acridine] (1.18 g, 2.0 mmol), 4′-(4,4,5,5-tetramethyl-1,3-dioxolan-2-yl)-[1,1′-biphenyl]-3-carbonitrile (1.35 g, 4.4 mmol), Pd(PPh₃)₄ (116 mg, 0.10 mmol), and sodium carbonate (2.12 g, 20 mmol) in DME (50 mL) and distilled water (10 mL) was refluxed for 24 h under argon. The mixture was then extracted with CH₂Cl₂. The combined organic extracts were dried over anhydrous MgSO₄ and concentrated by rotary evaporation. The crude product was purified by column chromatography on silica gel using 1:1 CH₂Cl₂/Hexanes (R_(f)=0.25) as eluent to afford a greenish-yellow solid. Yield: 73%.

Data for the compound of the formula (III-11′): ¹H NMR (400 MHz, CDCl₃) δ 6.75 (s, 2H), 7.05-7.09 (m, 1H), 7.12-7.14 (m, 4H), 7.19 (s, 3H), 7.30-7.40 (m, 10H), 7.46-7.48 (m, 2H), 7.55-7.58 (m, 3H), 7.60-7.62 (m, 2H), 7.78 (td, J=8.0 Hz, 1.6 Hz, 2H), 7.75 (t, J=1.6 Hz, 2H), 7.82 (d, J=7.6 Hz, 1H), 8.14 (dd, J=8.0 Hz, 0.8 Hz, 1H), 8.27 (t, J=7.6 Hz, 2H); ¹³C NMR (100 MHz, CDCl₃) δ 148.29, 141.87, 140.21, 139.52, 138.70, 138.46, 137.67, 135.44, 135.15, 133.32, 132.85, 132.54, 131.82, 131.32, 130.82, 130.55, 129.72, 127.98, 127.42, 127.32, 126.94, 126.40, 124.91, 123.77, 123.27, 122.35, 121.37, 121.13, 118.96, 113.91, 113.38, 113.10, 58.27; HR-MS calcd for C₅₉H₃₅N₃: 785.2831. found: 785.2834.

Example 12 Preparation of Compound of Formula (III-12′)

A mixture of 3,7-dibronmospiro[dibenzo[a,d][7]annulene-5,8′-indolo [3,2,1-de]acridine] (1.77 g, 3.0 mmol), cuprous cyanide (1.105 g, 12.0 mmol) in degasses DMF (12 mL) was refluxed for 18 h under argon. The mixture was then cooled to rt and concentrated under reduced pressure. An aqueous solution of ammonia (2M, 150 mL) was added and the mixture was extracted with CH₂Cl₂. The combined organic extracts were dried over anhydrous MgSO₄ (2.5 g) and concentrated by rotary evaporation. The crude product was purified by column chromatography on silica gel using 1:1 CH₂Cl₂/Hexanes as eluent to afford a yellow solid 1.015 g (yield: 70%).

Data for the compound of the formula (III-12′): T_(m) 388° C. (DSC); T_(g) 144° C. (DSC); TLC R_(f) 0.25 (EtOAc/hexanes=1/3); ¹H NMR (400 MHz, CDCl₃) 8.29 (t, J=8.0, 2H), 8.18 (d, J=8.0, 1H), 7.87 (d, J=8.0, 1H), 7.66 (t, J=8.0, 1H), 7.43 (t, J=8.0, 2H), 7.32-7.12 (m, 9H), 7.00 (t, J=8.0, 1H), 6.74 (s, 2H); ¹³C NMR (100 MHz, CDCl₃) δ 140.00, 138.32, 136.78, 135.11, 134.51, 134.36, 133.05, 132.65, 131.22, 130.82, 129.41, 128.80, 127.28, 125.91, 125.67, 124.05, 123.26, 122.86, 121.43, 121.25, 118.79, 118.25, 114.47, 113.53, 112.21, 57.28; HR-MS calcd for C₃₅H₁₉N₃: 481.1579. found: 481.1571.

Steady-State Photophysical Measurements

Absorption spectra were measured on a SP-8001 Diode Array spectrometer by using spectrophotometric grade CH₂Cl₂ (10 mM in CH₂Cl₂). Emission spectra (in 10 mM) were measured on (a FP-6500 luminescence spectrometer upon excitation at the absorption maxima of the longest absorption band in the same solvent. The emission spectra measured in CH₂Cl₂ (10 mM) were normalized by their emission maxima to the same intensity (maximum intensity 1). Fluorescence quantum yield (Φ_(f), %) calculation were integrated emission area of the fluorescent spectra and compared the value to the same area measured for Coumarin 1^(2c) (Φ_(f)=0.90, CH₂Cl₂) or Coumarin 6 (Φ_(f)=0.78, EtOH) in CH₂Cl₂ (in 10 mM). The quantum yields are calculated by using the following equation 1. Where A stands for area of fluorescent emission for sample (i.e. the compounds of formulas (III-1) to (III-3)) and Coumarin 1 or Coumarin 6; a is absorbance for sample and Coumarin 1 or Coumarin 6; and n is the refractive indices of solvent for sample and Coumarin 1 or Coumarin 6 (the refractive index (n) for CH₂Cl₂=1.42; for EtOH=1.36).

Φ^(sample) _(f)=(A _(sample) /A _(standard))×(a _(standard) /a _(sample))×(n _(sample) /n _(standard))²×Φ^(standard) _(f)  [Equation 1]

Cyclic Voltammetry (CV) Measurements

CV experiments were carried out with 1.0 mM of one substrate in a given anhydrous, degassed solvent containing 0.1 M tetrabutylammonium perchlorate or phosphate (n-Bu₄NClO₄ or n-Bu₄NPF₆) as a supporting electrolyte on a Chinstruments CH1604A potentiostat. A platinum wire electrode was used as a counter electrode, and a glassy carbon electrode was used as a working electrode. Ag/AgCl was used as a reference electrode.

Differential Scanning Calorimetry (DSC) Analyses

DSC measurements were performed on a SEIKO SSC 5200 DSC Computer/Thermal Analyzer. The samples were first heated (20° C./min) to melt and then quenched with liquid nitrogen. Glass transition temperatures (T_(g)) were recorded by heating (10° C./min) the cooled samples.

Thermogravimetric Analyses (TGA)

TGA measurements were performed on a SEIKO TG/DTA200 instrument by the Northern Instrument Center of Taiwan. Melting points were measured on a Hargo MP-2D instrument.

Property Evaluations of Compounds of Formulas (III-1′) to (III-12′)

The data of glass transition temperature (T_(g)), decomposition temperature (T_(d)), the longest peak wavelength value of absorption spectrum (λ_(max)), and the longest peak wavelength value of photoluminescence spectrum (PL λ_(max)) of the compounds of the formulas (III-1′) to (III-12′) are measured and recorded in the following Table 1. From the Table 1, it is able to know that these compounds provided by the present invention have glass transition temperatures (T_(g)) ranged from 118° C. to 163° C. and decomposition temperatures (T_(d)) ranged from 400° C. to 465° C. That means the compounds of provided by the present invention possess excellent thermal stability, and are not easy to decompose under high voltage and high current density operation conditions.

TABLE 1 Compound T_(g) (° C.) T_(d) (° C.) λ_(max) (nm) PL λ_(max) (nm) Formula (III-1′) 124 400 432 452 Formula (III-2′) 127 415 437 470 Formula (III-3′) 150 435 428 449 Formula (III-4′) 119 423 366 514 Formula (III-5′) 120 415 374 403, 552 Formula (III-8′) 118 429 431 460 Formula (III-9′) 135 439 437 477 Formula (III-10′) 132 441 365 461 Formula (III-11′) 163 465 374 426, 447 Formula (III-12′) 144 431 374 390, 523

Moreover, the oxidation potential and the reduction potential of the compounds provided by the present invention can be measured by way of cyclic voltammetry (CV); therefore, the highest occupied molecular orbital energy level (E_(HOMO)) and lowest unoccupied molecular orbital energy level (E_(L)) of the compounds provided by the present invention can also be calculated based on the measured oxidation potential (E_(1/2) ^(ox)) and the reduction potential (E_(1/2) ^(red)). With reference to following Table 2. E_(1/2) ^(ox), E_(1/2) ^(red), E_(HOMO), and E_(LUMO) of the compounds of the present invention are recorded. From the Table 2, the persons skilled in OLED material art are able to know that the compounds provided by the present invention have the E_(HOMO) ranged from 4.86 eV to 5.47 eV and the E_(LUMO) ranged from 2.16 eV to 2.74 eV. Moreover, the compounds provided by the present invention also have the oxidation potentials ranged from 0.06 V to 0.87 V or have the reduction potential ranged from −1.89 to −2.32 V.

TABLE 2 E_(1/2) ^(ox) E_(1/2) ^(red) E_(g) E_(HOMO) E_(LUMO) Compound (V) (V) (eV) (eV) (eV) Formula (III-1′) 0.68 — 2.74 5.48 2.74 Formula (III-2′) 0.28 — 2.64 5.08 2.64 Formula (III-3′) 0.67 −2.28 2.94 5.47 (5.79) 2.53 (2.85) Formula (III-4′) 0.74 −2.15 3.05 5.54 3.44 Formula (III-5′) 0.70 −1.91 3.21 5.57 2.36 Formula (III-8′) 0.69 — 2.70 5.49 2.79 Formula (III-9′) 0.06 — 2.70 4.86 2.16 Formula (III-10′) 0.87 −2.26 3.01 5.66 2.65 Formula (III-11′) 0.84 −2.32 2.93 5.64 2.71 Formula (III-12′) 0.76 −1.89 3.20 5.56 2.36

Furthermore, in order to prove that the compounds of the present invention can indeed be applied in OLEDs for being as a hole-blocking type electron transport layer, a plurality of OLED devices for control groups and experiment groups have been designed and manufactured.

All the materials were either commercially available or synthesized as described in this experiment and were subjected to gradient sublimation under high vacum prior to use. The substrate was an indium tin oxide (ITO) coated glass sheet with a sheer resistance of ˜30 W/□. Pre-patterned ITO substrates were cleaned sequentially by sonication in a detergent solution, doubly distilled water, and EtOH for 5 min in turn before being blown dry with a stream of nitrogen. The ITO substrate was then treated with oxygen plasma for 5 min before being loaded into the vacuum chamber. The organic layers were deposited thermally at a rate of 0.1-0.3 nm/s in a chamber (ULVAC, TU-12RE) under a pressure of 5×10′ Torr. Device were constructed with 40 nm of the hole transporting layer (HTL), 40 nm of the light-emitting layer (LEL), 10 nm of the hole-blocking layer (HBL), 40 nm of the electron-transporting layer (ETL), 1 nm of LiF as the electron-injecting layer (EIL), and 150 nm of Al as the cathode, respectively. In addition, 1,4,5,8,9,11-Hexaazatriphenylene-hexacarbonitrile (HATCN) is used as the HIL; 4,4′-Cyclohexylidenebis [N,N-bis(4-methylphenyl)benzenamine] (TAPC) is used as the HT01. Herein, the material used in each layer is summarized in the following Table 3.

TABLE 3 LEL Cathode EIL ETL HBL Blue dopant Host HTL Anode Embodiment 1 Al LiF Alq₃ BCP Formula BANE NPB/ HIL/ITO III-1′ HT01 Embodiment 2 Al LiF Alq₃ BCP Formula BANE NPB/ HIL/ITO III-2′ HT01 Embodiment 3 Al LiF Alq₃ BCP Formula BANE NPB/ HIL/ITO III-8′ HT01 Comparative Al LiF Alq3 BCP Formula 5A Formula 5A NPB/ HIL/ITO embodiment 1 HT01 Embodiment 4 Al LiF Formula BCP Formula 5A BANE NPB/ HIL/ITO III-3′ HT01 Embodiment 5 Al LiF Formula BCP Formula 5A BANE NPB/ HIL/ITO III-10′ HT01 Comparative Al LiF Alq3 BCP Formula 5A BANE NPB/ HIL/ITO embodiment 2 HT01

In the Table 3, Alq3 is the abbreviation of Tris-(8-hydroxyquinoline)aluminum, BCP is the abbreviation of 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline, and BANE is the abbreviation of 10,10′-di(biphenyl-4-yl)-9,9′-bianthracene. In addition, spirobifluorene is represented by following chemical formula 5A; and the compound of the following chemical formula 5B can also be used as the dopant emitter.

Furthermore, it is able to know that the materials of TPBi, DPyPA. BmPyPb, and ET01 recorded in the Table 3 are also used as OLED device's electron transport layers. However, the present invention is not limited thereto.

FIG. 2 is a perspective view showing the OLED devices provided above. The OLED device of the present invention comprises: a first electrode 12; a second electrode 18; and an organic layer disposed between the first electrode 12 and the second electrode 18. Herein, the first electrode 12 is a cathode, and a substrate 11 is disposed therebelow. The second electrode 18 is an anode. The organic layer comprises: an electron-injection layer 13, an electrode-transporting layer 14, a hole-blocking layer 15, a light-emitting layer 16, and a hole transporting layer 17, sequentially laminated on the first electrode 12.

Herein, Current-voltage-light intensity (I-V-L) characteristics and EL spectra were measured and recorded by PRECISE GAUGE, EL-1003; and the turn-on voltage (V_(on)), the external quantum efficiency (η_(ext)), the current efficiency (η_(c)), the power efficiency (η_(p)), and the maximum luminance (L_(max)) of the OLED devices are listed in the following Table 4.

TABLE 4 λ_(max) Von η_(ext) η_(c)/η_(p) L_(max) (nm) (V) (%) (%) (cd/m²) Embodiment 1 452 3.0 2.8 4.2/1.5 7563 Embodiment 2 452 3.0 3.1 4.3/1.8 6585 Embodiment 3 452 2.8 3.2 4.3/1.6 7960 Comparative 452 3.3 4.5 5.0/4.3 9898 embodiment 1 Embodiment 4 452 2.8 8.0 9.1/7.1 50000 Embodiment 5 452 3.4 7.5 8.0/6.6 54640 Comparative 452 3.4 2.6 2.0/0.8 5256 embodiment 2

With reference to the measured data of the blue fluorescent OLED devices in the Table 4, one can find that the OLED devices using double hole transport layer of Embodiments 1-3 show excellent η_(ext), η_(c), η_(p), and L_(max) and are comparable to the OLED devices using single emitting layer of Comparative embodiment 1. Among them, Embodiment 2 (Compound of formula (III-2′)) shows the best results, where the η_(ext) is 3.1%, η_(c) is 4.3 cd/A, η_(p) is 1.8 lm/w, and L_(max) is 6585 cd/m².

In addition, the measured data also reveals that the OLED devices using single dopant emitting layer of Embodiment 2 shows excellent η_(ext), η_(c), η_(p), and L_(max) and is superior to the OLED devices using single dopant emitting layer of Comparative embodiment 2. Moreover, the commercial OLED device using single dopant emitting layer of Embodiments 4 and 5 by using Compound of formula (III-3′) and (III-10′) as the ETL also shows excellent η_(ext), η_(c), η_(p), and L_(max), which is at least three times superior to the OLED devices using single dopant emitting layer of Comparative embodiment 2.

Furthermore, device life time evaluation tests for the blue fluorescent OLEDs have also been completed based on a starting luminance of 1,000 cd/cm². Life time evaluation test results reveal that the decay half lifetimes (LT₅₀) of the green phosphorescent OLED for Embodiment 4 is 903 hours. In addition, the decay half lifetime (LT₅₀) for the blue fluorescent OLEDs of Comparative embodiment 2 is measured as 930 hours.

In conclusion, the compounds of the present invention have glass transition temperatures ranged from 118° C. to 163° C., decomposition temperatures ranged from 400° C. to 465° C., reversible electron transport property, and balanced charges motilities.

Moreover, a variety of experimental data have proved that the compounds of the present invention can indeed be used as a hole-transporting type emitters and dopant emitters for OLEDs; moreover, the experimental data also reveal that the OLEDs using the compounds of the present invention are able to show good to excellent external quantum efficiency (η_(ext)), current efficiency (η_(c)), power efficiency (η_(p)), maximum luminance (L_(max)), and device lifetime performances better than the conventional or commercial OLEDs.

Furthermore, from the results shown in Table 4, it can be concluded that the compounds of the present invention, especially the compounds of the formulas (III-1) to (III-3), can be used as a dopant as well as a host emitter for the light emitting layer of OLEDs.

Except for the aforementioned OLED devices, the present invention also provides an organic solar cell, which is shown in FIG. 3. The organic solar cell of one embodiment of the present invention comprises: a first electrode 21; a second electrode 22; and an organic layer 23 disposed between the first electrode 21 and the second electrode 22 and comprising any one of the compounds of the formulas (III-1), (III-2), and (III-7). In the organic solar cell of the present invention, the organic layer 23 is served as a carrier transport layer.

Except for the aforementioned OLED device and organic solar cell device, the compounds provided by the present invention can be applied to various organic electronic devices, such as an organic thin film transistor, an organic photodetector, a flat panel display, a computer monitor, a television, a billboard, a light for interior or exterior illumination, a light for interiror or exterior signaling, a heads up display, a fully transparent display, a flexible display, a laser printer, a telephone, a cell phone, a tablet computer, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display, a vehicle, a large area wall, a theater or stadium screen, or a sign. However, the present invention is not limited thereto.

Although the present invention has been explained in relation to its preferred embodiment, it is to be understood that many other possible modifications and variations can be made without departing from the spirit and scope of the invention as hereinafter claimed. 

What is claimed is:
 1. A compound comprising: a 7-membered ring segment, which is formed by a cis-stilbene segment and a bridge atom with four bonds; and an acridine segment connecting to the bridge atom of the 7-membered ring segment.
 2. The compound of claim 1, wherein the bridge atom is C or Si.
 3. The compound of claim 1, which is represented by the following formula (I):

wherein, each of R₁ and R₂ independently is halogen, C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy, C₃-C₂₀ cycloalkyl, C₃-C₂₀ heterocycloalkyl, —NR_(a)R_(b), —CN, aryl, heteroaryl, carbazoyl, or —R_(c)-R_(d); each of R₃, R₄ and R₅ independently is H, halogen, C₁-C₁₀ alkyl, C₁-C₁₀ alkenyl, C₁-C₁₀ alkoxy, C₃-C₂₀ cycloalkyl, C₃-C₂₀ heterocycloalkyl, —NO₂, —OH, —NR_(a)R_(b), —CN, aryl, or heteroaryl; and Ar is an aromatic ring, wherein each of R_(a) and R_(b) independently is H, C₁-C₁₀ alkyl or aryl; R_(c) is aryl; and R_(d) is H, C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy, —CN or aryl.
 4. The compound of claim 3, wherein R₁ and R₂ are the same.
 5. The compound of claim 3, wherein R₁ and R₂ are —NR_(a)R_(b), and R_(a) is aryl, and R_(b) is C₁-C₁₀ alkyl or aryl.
 6. The compound of claim 5, wherein each of R_(a) and R_(b) independently is phenyl, naphthyl, or anthryl unsubstituted or substituted with C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy or —CN.
 7. The compound of claim 3, which is represented by the following formula (I-1):


8. The compound of claim 3, which is represented by the following formula (I-2):


9. The compound of claim 3, wherein R₁ and R₂ are the following substituent (II-1):

wherein X is H or C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy, or CN.
 10. The compound of claim 9, wherein X is H, methyl, ethyl, methoxy, or ethoxy.
 11. The compound of claim 3, wherein R₁ and R₂ are Br, pyridyl phenyl, naphthyl, anthryl or carbazoyl.
 12. The compound of claim 3, wherein R₁ and R₂ are phenyl unsubstituted or substituted with methoxy, ethoxy, or —CN.
 13. The compound of claim 3, wherein R₁ and R₂ are —R_(c)-R_(d), in which R_(c) is phenylene, R_(d) is phenyl unsubstituted or substituted with methoxy, ethoxy, or —CN.
 14. The compound of claim 3, which is represented by the following formulas (III-1) to (III-12):


15. The compound of claim 3, having glass transition temperatures (T_(g)) ranged from 118° C. to 163° C., decomposition temperatures (T_(d)) ranged from 400° C. to 465° C. and/or oxidation potentials ranged from 0.06 V to 0.87 V or the reduction potential ranged from −1.89 to −2.32 V.
 16. The compound of claim 3, which is applied to an organic light emitting device, an organic solar cell device, an organic thin film transistor, an organic photodetector, a flat panel display, a computer monitor, a television, a billboard, a light for interior or exterior illumination, a light for interiror or exterior signaling, a heads up display, a fully transparent display, a flexible display, a laser printer, a telephone, a cell phone, a tablet computer, a laptop computer, a digital camera, a camcorder, a viewfinder, a micro-display, a vehicle, a large area wall, a theater or stadium screen, or a sign.
 17. An organic electronic device, comprising: a first electrode; a second electrode; and an organic layer disposed between the first electrode and the second electrode, and comprising a compound comprising: a 7-membered ring segment, which is formed by a cis-stilbene segment and a bridge atom with four bonds; and an acridine segment connecting to the 7-membered ring segment by sharing the bridge atom, wherein the bridge atom in the compound is C or Si.
 18. The organic electronic device of claim 17, wherein the compound is represented by the following formula (I):

wherein, each of R₁ and R₂ independently is halogen, C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy, C₃-C₂₀ cycloalkyl, C₃-C₂₀ heterocycloalkyl, —NR_(a)R_(b), —CN, aryl, heteroaryl, carbazoyl, or —R_(c)-R_(d); each of R₃, R₄ and R₅ independently is H, halogen, C₁-C₁₀ alkyl, C₁-C₁₀ alkenyl, C₁-C₁₀ alkoxy, C₃-C₂₀ cycloalkyl, C₃-C₂₀ heterocycloalkyl, —NO₂, —OH, —NR_(a)R_(b), —CN, aryl, or heteroaryl; and Ar is an aromatic ring, wherein each of R_(a) and R_(b) independently is H, C₁-C₁₀ alkyl or aryl; R_(c) is aryl; and R_(d) is H, C₁-C₁₀ alkyl, C₁-C₁₀ alkoxy, —CN or aryl.
 19. The organic electronic device of claim 17, wherein the organic electronic device is an organic light emitting device, and the organic layer is a hole transport layer, an electron transport layer or a light emitting layer.
 20. The organic electronic device of claim 17, wherein the organic electronic device is an organic solar cell device, and the organic layer is a carrier transport layer. 